The present invention relates generally to recording and/or reproducing apparatus including a mechanism for adjusting a tape guide. More particularly, the invention relates to a tape guide adjusting mechanism for use in a recording and/or reproducing apparatus of an automatic tape loading type. The tape is automatically drawn from a tape cassette and loaded in a predetermined tape travel path.
In general, there have been helical-scanning recording and/or reproducing apparatus wherein a video signal is recorded and reproduced by one or more rotating video heads. Recording tracks are made on and reproduced from a magnetic tape along a plurality of mutually parallel tracks, disposed obliquely relative to the longitudinal direction of the tape. In a recording/reproducing apparatus of this type, it is necessary for the magnetic tape to travel accurately along a predetermined tape path over the cylindrical surface of a guide drum surrounding one or more rotating video heads, so that the rotating heads form the correct track pattern on the magnetic tape during recording or trace over the correct tracks during reproducing.
The travel path of the tape over the cylindrical guide drum surface is determined by a tape guide mechanism. The mechanism extends from the inlet side of the guide drum cylindrical surface, that is, the supply side, to the outlet side of the guide drum cylindrical surface, that is, the take-up side. Accordingly, it is necessary to adjust the tape guide mechanism in order to cause the tape path to coincide accurately with the desired or predetermined tape path.
In known recording/reproducing apparatus, guide poles having flanges have been used for guiding the edges of the tape. An adjustment of the tape path has been accomplished by adjusting the height positions of these guide poles, relative to the chassis base, and at the points where the tape is guided by the tape guide poles.
However, it is troublesome to adjust the heights of the guide poles. Such an adjustment, requires high skill, and cannot be easily carried out. Furthermore, when the height of a guide pole is adjusted, its flange imparts an excessive force upon the edge of the tape. Then, the tension in the tape becomes non-uniform in its transverse direction. In extreme cases, the tape undergoes a deformation such as bending.